For all of its wild popularity, caffeine is one seriously misunderstood substance. It's not a…
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Everyone metabolizes caffeine differently, but how much you drink can play a big role in how it affects you—a little coffee in the morning and you'll be a bit more awake, but too much and you can develop anxiety and irritation. A recent review of over 200 studies found that about 400mg of caffeine per day—about three 8oz cups of coffee—is a safe dose for most adults to avoid these problems (though it would probably take nearly 75 cups over a few hours to truly overdose). How much caffeine do you drink in a day? Do you ever go "overboard" and start getting jittery? Let us know in the discussions below, and check out the link for more info on the research.